Self Cleaning Plastics

Have you ever put vegetables in the fridge for too long and the Saran wrap that you wrapped them in got all soggy? You're not alone. What if you never had to worry about dirty, microorganism infested plastics? What if the plastic just cleaned itself? This could save companies millions of dollars and put money back in consumers pockets, as they wouldn't have to go back to the grocery store to buy more food.This isn't far from reality thanks researcher led by Lukas C. Gerber at ETH Zurich. 

These Swiss researchers have isolated the fungus from blue cheese -yes, blue cheese - called peniciliium roqueforti and injected it into very thin porous sheets of plastic. The theory was to make plastic protect itself from unwanted bacteria, just like peniciliium roqueforti does to protect the cheese on the inside of a rind.

This could make dish detergents, soaps and sponges extinct!!  In fact, this novel material was called the "first eating material" and was recently described in the Proceedings of the National Academy of Sciences.

To prove that their theory of "self-cleaning plastic" was indeed possible, the researchers put a small amount of sugar solution on the plastic and let it go to work. They said in their recently published paper that "“Gas exchange for breathing and transport of nutrient through a nano-porous top layer allowed selective intake of food whilst limiting the microorganism to dwell exclusively in between a confined, well-enclosed area of the material,”

What shocked most people was that two weeks later, the sugar solution had been completely consumed by the fungus, leaving the plastic perfectly clean.  

So, you may be asking "now that the fungus has eaten all the sugar solution, will it continue eating the plastic?" The answer is no. In fact, with nothing to feed on the fungus went dormant again. Incredible!

Yes, two weeks for a plastic material to clean itself might seem like a long time but there are endless applications for this in the marketplace. A lot of the time, salmonella bacteria get's into leafy vegetables that are packaged. If they were wrapped in this type of plastic, the bacteria could possibly reduce food borne bacteria and save millions. Also, what if you went on vacation and came back to moldy bread? The fungus in the plastic could prevent the mold from overgrowing and spoiling all the bread..saving you money. 

This is not the first time though I have heard of fungus' being used with plastics. Last month I read an article about how students from Yale University discovered a fungus in the Amazon that can break down and utilize plastic. According to their research, the pestalotispsis microspora fungi can break down the common plastic called polyurethane. This is incredible as polyurethane plastics cannot be recycled because they cannot be remelted -once formed, they are that way forever. Airplanes are an example of this kind of plastic.

Unlike the polyurethane eating plastic, this "self cleaning plastic" contains a fungus that doesn't break down the plastic as well.

The world of plastic innovation continues to inspire and amaze me.